Bubbee-mixee



D. R; BOWEN AND C. F. SCHNUCK.

-RUBBER MIXER.

APPLxcATmN FILED JAN. 13. m19.

Patented Oct. 19, 1920.

4 'SHEETS-SHEET` I.

fil-QM.;

D. R. BUWEN AND C: F. SCHNUCK.

RUBBER'IS'HXHLv APPLICATION msn 1m13.191s.

1,355,885, Patented Oct. 19, 1920.

4 SHEETS-SHET 2.

'0. R. BOWEN AND c. F. SCHNUL..4

RUBBER MIXER.

ArPucArloN HL'ED JAN.13.1919.

D. R. BOWEN AND C. F. SCHNUCK.

RUBBER MIXER.

APPLlcAloN FILED uw. 13, 1919.

1,355,885. Patented Oct. 19, 1920.

4 SHEUSWSHEET 4.

UNITED STATES PATENT OFFICE.

Devin n. Bowen moonen u. sommen, or Ansturm, comcrrcu'r.- nssmfifon .Tounam. sommier No mesma comrm, or iiNsoNm, oonriiic'rrcur, Y con.;

numana-Mixen.

POBATION 0F CONNEOTIOUT.

Specification. of Letters Patent. Patented Oct. 19, 1920.

Application led. January 18,1919.. (Serial Itl'e.` 270,887.

To all whome't meer` concer-n: i

Be it known' t 'atY we Dnvrn R.l BOWEN sind CARL F. Scannen, bothcitizens of.' the United States, and both residing"v in An.- eonia,county of N ewl Haven, State lof Connecticut, have invented certain' newand useful Improvements iii Rubber-Mixers. of which the following is afull, clear, and exact description.

This invention relates to machines for mixing or inasticating heavyplastic material, and it has special reference to a machine for use inrubber manufacture, wherein rubber, (usually1 in the form of ratherlarge chunks), Vis reduced and mixed with a powdered filler or coloringagent.` The present improve ments relate more especially to the meanswhereby the materiel to be treated isjintro- 'duced or chargedinto theworking chamber in which the mixing operation' talr place iindcrtheaction of e suitable roter mixing element. The material is worked ackand,

forth in the chamber by one or more blades on the rotor until the rubberis reduced tio 'the desired plasticity sind the powder is thoroughly anduniformly incorporated therewith.

One oi the innin objects of our invention is to fi'irni'sh a. machine ofthis type wherein the material can be `charged .intoJ the chamber in nvery simple, convenient an satisfactory manner.

Another object of the invention is to fui'- iiish a machine in which theblowing out of the powder from the mixing chamber during the operationof mixing is avoided. Heretofore, it has been customary to hold the massagainst the rotor bladesby meansV of a piston o1' similar pressuredevice or 01-, lower, du ring the rotation ofthe rotor. An arrangementof that kind has the disadvantaste .that owing to the displsiceune'nt'of air substantially throiiirhoutthe interior of the mixing chamber,diie to the movement ci.

the piston or the like, the fine powderl is' blown out of the chamberthrough any smell cracks' or leaks that may 'Under these circumstances,it has been consid-V ered necessary to malte the mixing chamber asair-tight as possible duringfthe mixing, but the results havenotbeenjsatisfactory, in spite of the care taken 'and the' exnenjseincurred in providing tirrht joints and beni ings, Thepowder used inmixing rubber worln'ng conditions so isagreeeble and un-V licalthfii-l.The blowing of the owder into and through the bearings of t e mixer isalso highly undesirable onaccount of the difliciilty of keeping therotor shaft proper] lubricated.

e nini of our invention is to overcome the Vabove mentioned drawbacks byprovidin ,a machine, and e method of o erating t e same, whereby therubber an powend held in contact with the rotor without the use of anymovable ressu-re means other than the rotor itself. e rubber and thelder are charged4 into the mixing chamber i oivder are both fed into themixing cham'- er by grvityin connection with a certain amount ofagitation or drawing in action rocluced b the rotor in its rotation. Ad-

itionnl ru ber or edditionl powder or both can beedded to the batch ntany time diirm mixing in a most convenient wey andt e formation of enobjectionable dust cloud is avoided atell times.

To these and other ends the invention consists in the novel features andcombina;- tions of parts to -be hereinafter described und claimed.

In the accompanyingdrawings: Figure 1 is a front elevation of a rubbermixer embodying our invention. Fig. 2, isun .end elevation of the semeIooke' from the left of Fig. 1.

Fig; 3 is an end elevation lookingfrom the feed hopper.

Figs. 9 and 10 are details of the rotor, and

Figs. 11 and 12 are a vertical longitudinal section and a sectional endelevation respectively of a machine of somewhat modi fied form.

In theI present machine, the casing 20, having the mixing chamber, is ofgenerally cylindrical shape and is mounted by lugs 21 on a pair of sideframes 22. The mixing lhamber has heads 23, 24, which close the chamberor cylinder at the respective ends. A rotary mixing element or rotor 25having a horizontal shaft 26 with bearings 27, 28, in the respectivecylinder heads is arranged within the mixing c linder. The mixer casingis divided horizontally in a lengthwise direction and includes an uppersection 29 and a lower section 30. The mixing chamber is provided withan intermediate transverse extrusion rib 31. The rotor 25 is providedwith blades 25'* diametrically located on the rotor shaft, one of saidblades being located on one side of the extrusion rib and the otherbeing located on the other side. These blades are arranced at such anangle on the shaft as to worli the material back and forth in the mixingchamber and squeeze it through the space between the extrusion rib andthe intermediate part of the rotor. The blades make substantial contactwith the respective end walls of the mixing chamber and each blade hasa. workingl face whih forces the material against one side of the ribtoward the center of the chamber. In this manner the material is pressedand squeezed back and forth in the mixing chamber by the rotor blades.It will be observed that the length of the mixing chamber is small whenthe diameter of the chamber is considered, the extrusion rib takinfz upthe greater part of the length of the chamber side wall. The anglebetween the rotor blade and the' rotor axis is approximately in theembodiment shown in Figs. 1-10.

The charging opening into which the rubber and powder are introduced islocated in one of the cylinder heads. In the form shown` it is locatedin the upper part of the cylinder head 24, and is indicated at 32. Theheads 23, 24- are preferably formed separately from the side wall of themixing chamber and are held detavhably in place by bolts or the like,which we have not considcred it necessary to illustrate. The charging,ropening 32 is located at the lower part of a. charging hopper 33, whichin this instance is formed as an integral part of the head 24, in thatpart of the head located above the rotor shaft. The o enin 32 isimmediately adjacent an end e ge o one of the blades 25 at some timeduring the rotation of such blade and is arranged to be opened andclosed by the blade in its rotation, as shown more particularly iu Fig.8.

The blade has at its end a substantially dat surface 25", which rotatesin contact with the inner face of the cylinder head. This substantiallydat blade surface cuts oil or reduces the charging opening during asmall fraction of the rotation of the blade and then as said flatsurface passes beyond the charging openi the latter is uncovered and theIrmteria in the hopper 33, which passes d own into the bottom of saidhopper y 'aint drops into the void at the rear sur noe o the blade,whence it is taken up by the blade on its further rotation andthoroughly mixed by being forced against the side wall of the chamber,es previously described.

It will be ob rved that the leading portion of the bla e, which islocated adjacent the charging o ening, is approximately ierpendicular tot e rotor axis, as shown in tig.

8, so that the blade is adapted intermittently to cut oil the incomingmaterial.

At the lower part of the mixing chamber a suitable closure is providedfor controlling the discharge after mixing. This closure may take theform of a rotary valve 3-1, such as described in our application, SerialNo. 208,635, but it will be understood that the means for dischargingthe chamber forms no part of the present invention.

The casing and rotor are preferably pro vided with passages for thecirculation of cooling Water, so that the vulcanization of the rubber,due to heat generated by friction, fen be prevented.

The operation of the machine is substantially as follows:

Sup osing that the dischar e closure 34- is 1n t e closed position and tat the rotor 1s rotatin the rubber is charged into the chamber y way ofthe hopper 33 und the powder is then fed in after it through the samehopper so as to bc incorporated with the rubber as the latter is reducedto a plastic mass. This is a convenient way of .starting the operation,but it will be understood that the rubber and powder can be introducedat the same time, if desired, or the powder may be introduced first.iVhen the material is dumped into the hop er 33, it will be momentarilyheld in the opper if the dat surface 25 of the adjacent rotor blade isopposite the chargi opening, but if not, the material either rub i r orpowder or both, will pass freely into the interior of the mixingchamber, partly by gravity and partly owing to the agitation or drawm inaction produced by the rotation of the bide in the mixing chamber. Thematerial thus passes freely into vacant space or void at the rear of theblade and it is taken up by the front face of the blade on furtherrotation of the latter and squeezed against the extrusion rib andextruded between said rib and the rotor toward and past the center lOl)mmm a dtfthnhnmbenwhmnpunmch 1E um um. up y mma m mmm@ of Y(flueehnmibar m fammi hack aguil, thm

u mm mun *mm um mixgopemtirm ha raputad fing chmmlm'. Tha at tha my.Whnm bnhhubni VI n I mp und locate in Mub- 'm mimmtialaahm: imm'khmmmbymv' thevulve tuthaopenpaaiinn, m vri-hhthnmixing chamber. The :us Ehmn hop is m'rind by om u! the uynder Wih n bath. afnopm sin in the ehm;-h in falxrs pw funn, md it mn 1u gent Lemrofvtg wrm' he onnmmty mule mann :f ml. pprt 'ro 25# munt oom :M l ilarl 11m-inli and in auch 51mm YInw pmsaura tamed by the matutina of tha blades, into whih um the:maine-rial y1bn be ui mixed can ha mndly ntrodu. it has been found thatin the v;|r.m't.x;uz uf miamq than: is nu expukm: mi puwdr tlwnug .dwshrg opssning im spiga nfl the fmt tlmtthpluegtvpqmmand attire 20 hlmberla MmmmI i in thu general :11.1 w? n n; nml elm'gmg anisng. ,Before themnbmllboumnh th `m1''ngclsmn Bansin a idu It is ghi up by the. other hlgS5 and fawn haci: n nrn mtu tha Euh man s my um; v t n tn .'ow mit afthe ehn so via supplied to thm galnmhem. it

opening, I 0m' mvmmnu 1s a! cunsdenbla mgm'- vfar ma it ummm@ the hnwmguur: oma. n 'mimmhln mit cloud imm the 46 ta man mnnhirma, um im m :hn-

it. slmpi the ummm-:tim ai tha mmhmvm'y materiuly :md nachlass im anni.n

im In Figa. .Ll nnd'mmn have uhmm@ modlmtion ni wherein tlm mms versamitruaiqn rib in omitted. In this 082e, Ytlm chamba" 351mm ar @1in immmhim against whiuh the mnfmrnl is mmshntl as or mumb blanks 35, jwhlls beimam bmah :mrl fu. 11. The; ayl'lindr he 3?', hoffa'emj, is pmvdd with .ncharging 0pm 38 and kapper 39 snlm tu than pmvlnus described. In this:man im EY n |30 opening is ,located above the Bwf: w,

viii is l'fmulilyv mumshlo fm' the introdmtiub.

-rit tlm rubin? :m gil-wrdn the mrt hengswh that: tlm mma mmm many Immthe: kapper inw tbn ,mixing uhmm isa wtbmxt having m panthrough :myintarqf the ylindw In n mdinl Ellmtwn the pmmg nl; the of the bamm benda'lhs innm' au nf tIbu mmn-g ehnmlm aida wall, n praximntmg in radikalmast tha ,mum Ill www; h immer mrfma uf the nhnmher ch 'ng @gung-'7, nmy rah apno glna a dimm hom'wumenV the ohnmand wall ami bhs mlm*I shaft.om'

n mgm! uf the invention m unimuthara portant .Wqo nu# claim bcmldll' hwithe mm hmntmn 0f u working chlmbmblatled www and. tn'nugmsa rh, uachilmd in our ngplmtnn Ssrnl Nm HLM; nur da we du@ hrulidly 'imnn thismmhrinntian of n wm'kmylhmmbah und n hlmlad natur in aan] ulmmny mfm'mnvin this mma-inl had: und ful-th, smid lumber v wing am punit-gmammwallarthnpgrmofulmwill! ;V. l @Pulling QI la th* manfthrobm'blmds,ns cllmed our r y 'wu Swim] No. www, mr sinA n c nim broadly herein thufutura ad pmvin n hmgu contnnm Matha md of the wmf g chamber bn ma mwauf mbbm tu bu mppld tn mid wmkmg chnmlmrnmd and .mid hugs mmm being ndime#` ccmmtmpnbm with auch nthm' b. Y

:um tha mma? which tlm mbbm aimais to be mami panhmly mi directly immthe emgtnmro tlm wur-king chamba ne gluem m nur nmiann fn.

120 R minus changs lmp' bu made in the demiie uf thu mnnhlu 'Wlilmwdlartn imm thu scope of our in., nl in 'the afirmwhat we daim is:

1. In n mhbm mima'.h n walkin dumber, u Mtnl tlmwin bmi blnda mnviimmaterial html: and lin smid uhqm'ber, dm'mhm' having am opening inune. o! its end walls im' than funding in of nutmal 1&0

to be treated, and a hop r on the end wall of the chamber, said opperhaving an opening at its inner side coinciding with said first namedopening.

2. In a rubber mixer, a working chamber, a rotor shaft therein havingblades for moving the material back and forth in said chamber' saidchamber having an opening in one o its end walls located substantiallyabove said shaft for the introduction of rubber and wder.

3. In a rubober mixer, a working chamber, a rotor shaft therein havingblades for moving the material back and forth in said chamber, saidchamber having an opening in enc of its end walls located substantiallyabove said shaft for the introduction of rub ber and iowder, and ahopper on the end wall of tlic chamber open at its inner side and indirect communication with said first named opening.

4. In a rubber mixer, a working chamber, a rotor therein for moving thematerial back and forth in said chamber, said chamber having adetachable head, and an open sided hopper carried by said head and indirect communication with the interior of the chamber.

5. In a rubber mixer. a working` chamber, a rotor therein having bladesfor forcing the material alternatel back and forth in said chamber, anda etachable head for said chamber having a charging openins.r and anopen sided hopper integral with the head in proximity to said opening.

6. In a rubber mixer, a working chamber, a rotary mixing element thereinhaving blades for forcing the material alternately from one end of thechamber to the other, said chamber having an end onenin" of considerablesize located substantially above the rotor sha-ft for the introductionof rubber and powder. the denth of s-iid omni proximating the radialdistance from the inner surface of the chamber side wall to the rotorshaft.

7. In a rubber mixer, the combination of a casing providing a workingchamber, a horizontal rotor in said casing having blades for working thematerial from one end of the chamber to the other and back again, saidchamber havin" an opening in one of its end Walls for the introductionof rubber and powder controlled by one o f said blades, said openingapproximating in depth the distance between the inner surface of thechamber side wall and the body of the rotor.

8. In a rubber mixer, the combination of a casing providing a workingchamber, a horiaontal rotor in said casini: having blades for workingthe material from one end of the chamber to the other and back again.said chamber harinar an opening in one of its end walls for theintroduction of rubber and powder controlled by one of said blades, saidopening approximating ,in width the distance between the inner surfaceof the chamber side wall and the body of the rotor.

9. In a rubber mixer, the combination of a casing providing a workichamber, a horizontal rotor in said casio" avinir blades for working thematerial from one end of the chamber to the other and back again, saidchamber having an o ning in one of its end walls for the intro uctioiiof rubber and powder controlled by one of said blades, said openingapproximating in depth and width the distance between the inner surfaceof the chamber side wall and the body of the rotor, wherebycomparatively large chunks of rubber may be introduced into the chamberby way of said opening.

10. In a rubber mixer, a casing providing a workinechamber, a horizontalrotor in said cham r for moving material back and forth, said chamberhaving a detachable end wall with an opening therein for theintroduction of rubber chunks and powder, said opening approximating indepth and with the distance between the inner surface ofthe chamber sidewall and the rotor body, and a hopper on the end wall having a si eopening coinciding with said first named openin l1. e method of mixingrubber, which comprises working the mass against the side wall of amixing chamber by means of a rotating blade, and introducing rubber undpowder into the chamber in the void at the rear face of the bladethrough the end wall 0f the chamber.

12. The method of introducing material to be mixed into a rubber mixerhaving a mixing chamber and a rotary blade therein, which comprisesfeeding all of the ingredients of the mixture directly into the spacebehind the rotating blade.

13. The method of introducing material to be mixed into a rubber mixerhaving a mixing chamber and a rotary blade therein, which comprisesfeeding all of the ingredients of the mixture directly into the spacebehind the rotatingblade through the end wall of the mixing chamber.

14. The method of mixing rubber in a mixer having a mixing chamber androtating blades therein for working the material back and forth in saidchamber` which com prises feeding rubber and powder through one of theend walls of the mixing chamber into the vacant space at the rear of oneof the blades.

15. The method of mixing rubber in e mixer having a mixing chamber androtating blades therein for working the material back and forth in saidchamber, which comprises feeding rubber chnnks through one of the endWalls of the mixing chamber into the vacant s ace at the rear of one ofthe rotatinflr bla es.

16. he method of mixing rubber in a suitable mixing chamber by means otrotating blades which Work the material back and forth in said chamber,which comprises feeding rubber and powder by gravity directly into theend of the mixing chamber at a point in the path of rotation ot' one ofsaid blades, so that the rubber and powder can be drawn into the spaceat the rear of the rotating blade.

1T. The method of mixing rubber which comprises Workin the mass againstthe side wall of a mixing chamber by means of a rotating blade andintroducing additional rubber into the chamber in the void at the rearface of the rotating blade during the mixin 18. n a rubbeil mixer, aworking cham ber, a rotor therein having blades which force the materialback and forth in said chamber, the diameter of the chamber beingcontinuously-reduced from substantially` the ends thereof to the middleof said chamber.

19. In a rubber mixer, a working chamber symmetrically reduced in crosssection substantially from the ends to a point intermediate the ends.and a rotor Working in said chamber having mashing blades to mash thelmaterial against the side Wall of the chamber.

20. In a rubber mixer, a working chamber, a rotor therein for Workingthe material back and forth, and an extrusion rib extendingsubstantially throughout the length of the chamber.

21. In a rubber mixer, a mixing chamber of relatively largediametercompared to its length having an interior transverse extrusion ribtaking up the greater part of the length of the chamber side Wall. and arotor in said chamber having blades ed operating with said rib.

22. In a machine of the character de scribed, a Working chamber. havinga i'eed opening at the end` and a rotor in said chamber for Working thematerial baek and forth, having a blade with a leading end portionadjacent said charging opening arranged approximately perpendicular tothe rotor axis.

23. In a machine of the character diL scribed, a Working chamber in theshape oi a drum. the length of which is no greater than the diameter,and a rotor in said chamber having blades for Working the material backand forth in the latter, said blades with their leading endsapproximately perpendicular to the rotor shaft.

24. In a rubber mixer, a Working chamber, a` rotor therein for Workingthe material back and forth, and blades on said rotor arranged at anangle of approximately 80 to the rotor axis.

25. In a rubber mixer. a mixing chamber 'of considerable diametercompared to its length having an extrusion rib taking up the greaterpart of the length of the chamber, a rotor in said chamber. and bladeson said rotor eoperating with said rib at opposite sides thereof andarranged at an angle of approximately 80 to the rotor axis.

